RT info:eu-repo/semantics/article
T1 Evidence for the nuclear import of histones H3.1 and H4 as monomers
A1 Hernández Fernaud, Juan Ramón
A1 Apta-Smith, Michael James
A1 Bowman, Andrew James
A2 BioquímicaMicrobiología, Biología Celular y Genética
A2 School of Life Sciences. University of Warwick.
K1 chaperone
K1 chromatin
K1 histone
K1 nuclear import
K1 nucleosome
AB Newly synthesised histones are thought to dimerise in the cytosol and undergo nuclear import in complex with histone chaperones. Here, we provide evidence that human H3.1 and H4 are imported into the nucleus as monomers. Using a tether-and-release system to study the import dynamics of newly synthesised histones, we find that cytosolic H3.1 and H4 can be maintained as stable monomeric units. Cytosolically tethered histones are bound to importinalpha proteins (predominantly IPO4), but not to histone-specific chaperones NASP, ASF1a, RbAp46 (RBBP7) or HAT1, which reside in the nucleus in interphase cells. Release of monomeric histones from their cytosolic tether results in rapid nuclear translocation, IPO4 dissociation and incorporation into chromatin at sites of replication. Quantitative analysis of histones bound to individual chaperones reveals an excess of H3 specifically associated with sNASP, suggesting that NASP maintains a soluble, monomeric pool of H3 within the nucleus and may act as a nuclear receptor for newly imported histone. In summary, we propose that histones H3 and H4 are rapidly imported as monomeric units, forming heterodimers in the nucleus rather than the cytosol.
YR 2018
FD 2018
LK http://riull.ull.es/xmlui/handle/915/38875
UL http://riull.ull.es/xmlui/handle/915/38875
LA en
DS Repositorio institucional de la Universidad de La Laguna
RD 08-ene-2025